// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/mac/dispatch_source_mach.h"

#include <mach/mach.h>

#include <memory>

#include "base/logging.h"
#include "base/mac/scoped_mach_port.h"
#include "base/test/test_timeouts.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace base {

class DispatchSourceMachTest : public testing::Test {
public:
    void SetUp() override
    {
        mach_port_t port = MACH_PORT_NULL;
        ASSERT_EQ(KERN_SUCCESS, mach_port_allocate(mach_task_self(), MACH_PORT_RIGHT_RECEIVE, &port));
        receive_right_.reset(port);

        ASSERT_EQ(KERN_SUCCESS, mach_port_insert_right(mach_task_self(), port, port, MACH_MSG_TYPE_MAKE_SEND));
        send_right_.reset(port);
    }

    mach_port_t GetPort() { return receive_right_.get(); }

    void WaitForSemaphore(dispatch_semaphore_t semaphore)
    {
        dispatch_semaphore_wait(semaphore, dispatch_time(DISPATCH_TIME_NOW, TestTimeouts::action_timeout().InSeconds() * NSEC_PER_SEC));
    }

private:
    base::mac::ScopedMachReceiveRight receive_right_;
    base::mac::ScopedMachSendRight send_right_;
};

TEST_F(DispatchSourceMachTest, ReceiveAfterResume)
{
    dispatch_semaphore_t signal = dispatch_semaphore_create(0);
    mach_port_t port = GetPort();

    bool __block did_receive = false;
    DispatchSourceMach source("org.chromium.base.test.ReceiveAfterResume",
        port, ^{
            mach_msg_empty_rcv_t msg = { { 0 } };
            msg.header.msgh_size = sizeof(msg);
            msg.header.msgh_local_port = port;
            mach_msg_receive(&msg.header);
            did_receive = true;

            dispatch_semaphore_signal(signal);
        });

    mach_msg_empty_send_t msg = { { 0 } };
    msg.header.msgh_size = sizeof(msg);
    msg.header.msgh_remote_port = port;
    msg.header.msgh_bits = MACH_MSGH_BITS_REMOTE(MACH_MSG_TYPE_COPY_SEND);
    ASSERT_EQ(KERN_SUCCESS, mach_msg_send(&msg.header));

    EXPECT_FALSE(did_receive);

    source.Resume();

    WaitForSemaphore(signal);
    dispatch_release(signal);

    EXPECT_TRUE(did_receive);
}

TEST_F(DispatchSourceMachTest, NoMessagesAfterDestruction)
{
    mach_port_t port = GetPort();

    std::unique_ptr<int> count(new int(0));
    int* __block count_ptr = count.get();

    std::unique_ptr<DispatchSourceMach> source(new DispatchSourceMach(
        "org.chromium.base.test.NoMessagesAfterDestruction", port, ^{
            mach_msg_empty_rcv_t msg = { { 0 } };
            msg.header.msgh_size = sizeof(msg);
            msg.header.msgh_local_port = port;
            mach_msg_receive(&msg.header);
            LOG(INFO) << "Receieve " << *count_ptr;
            ++(*count_ptr);
        }));
    source->Resume();

    dispatch_queue_t queue = dispatch_queue_create("org.chromium.base.test.MessageSend", NULL);
    dispatch_semaphore_t signal = dispatch_semaphore_create(0);
    for (int i = 0; i < 30; ++i) {
        dispatch_async(queue, ^{
            mach_msg_empty_send_t msg = { { 0 } };
            msg.header.msgh_size = sizeof(msg);
            msg.header.msgh_remote_port = port;
            msg.header.msgh_bits = MACH_MSGH_BITS_REMOTE(MACH_MSG_TYPE_COPY_SEND);
            mach_msg_send(&msg.header);
        });

        // After sending five messages, shut down the source and taint the
        // pointer the handler dereferences. The test will crash if |count_ptr|
        // is being used after "free".
        if (i == 5) {
            std::unique_ptr<DispatchSourceMach>* source_ptr = &source;
            dispatch_async(queue, ^{
                source_ptr->reset();
                count_ptr = reinterpret_cast<int*>(0xdeaddead);
                dispatch_semaphore_signal(signal);
            });
        }
    }

    WaitForSemaphore(signal);
    dispatch_release(signal);

    dispatch_release(queue);
}

} // namespace base
